fpga: zynqpl: Flush dcache only for non-bitstream data

In case of aes decryption destination address range must be flushed
before transferring decrypted data to destination.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Signed-off-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/fpga/zynqpl.c b/drivers/fpga/zynqpl.c
index 90bb850..a11e485 100644
--- a/drivers/fpga/zynqpl.c
+++ b/drivers/fpga/zynqpl.c
@@ -548,8 +548,9 @@
 	 * Flush destination address range only if image is not
 	 * bitstream.
 	 */
-	flush_dcache_range((u32)dstaddr, (u32)dstaddr +
-			   roundup(dstlen << 2, ARCH_DMA_MINALIGN));
+	if (bstype == BIT_NONE && dstaddr != 0xFFFFFFFF)
+		flush_dcache_range((u32)dstaddr, (u32)dstaddr +
+				   roundup(dstlen << 2, ARCH_DMA_MINALIGN));
 
 	if (zynq_dma_transfer(srcaddr | 1, srclen, dstaddr | 1, dstlen))
 		return FPGA_FAIL;